分形理论是非线性系统理论中最为活跃的分支之一，研究的是复杂系统产生的不光滑、不可微分的复杂几何体。

Fractal theory is the most active branch of the non-linear science, what it concerns is non-smooth and non-differential geometry produced by complex systems.

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接着，利用函数的上次微分构造了不可微向量优化问题（VP）的广义对偶模型，并且在适当的弱凸性条件下建立了弱对偶定理。

Finally, the generalized dual model of the problem (VP) is presented with the help of upper subdifferential of function, and a weak duality theorem is given.

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本文提出了基于微分-积分方程组求解n - S方程的有限差分法求解不可压缩实际粘性流体绕孤立翼型流动。

A finite difference method based on differential-integral equation is presented for the solution of Navier-Stokes equations for incompressible viscous flow.

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